package spec.asumuliu.unit5;

import spec.asumuliu.unint3.Student;

import java.util.ArrayList;
import java.util.Collection;

public class CollectionTest {
    public static void main(String[] args) {
        Object o =new ArrayList();
        Collection c =new ArrayList();
        Student s1=new Student("张三","123456");
        Student s2=new Student("李四","123457");
        Student s3=new Student("王五","123458");
        System.out.println(c.size());//0
        System.out.println(c.isEmpty());//true

        ArrayList a = new ArrayList();
        if(a==c){
            System.out.println("a和c相等");
        }
        a.size();
        c.size();
        a.listIterator();
//        c.listIterator();
        System.out.println(c.size());//1
        System.out.println(c.isEmpty());//false
    }
}
